Packing and process



Nom 29, 1932. H. s. WALKER PACKING AND PROCESS Filed March29, 1950- 'lllllllll/ll;

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@1I/tonnage Patented Nov. 29d, 1932 UNITED STATE-s APATENT- OFFICE HEBBEBT STANLEY WALKER, OF LARCHMON T, NEW YORK, ABSIGN'OB T0 THE 'ALIJAX 4 COMPANY, INC., 0F MAILARONECK, NEW YORK PACKING AND rnocnss `Application led March 29, 1930. Serial No. 440,058.

The invention relates to a new and improved packing for shafts, rods and the like, and it relates more particularly to a packing of strand or rope-li e form.

The general practice of producing strand or ro e-like packing embodies numerous steps 1n the production of asbestos or other yarn, entailing carding, spinning, twisting and winding. The yarn, after-manufacture is lubricated and twisted to various diameters to produce desired sizes of packing, and while such packings are ecient and well lubricated for a short while, in little time the lubricant is completely pressed out or melted by heat, leaving only the dry yarn in contact with the rod or shaft. rlhis is necessarily injurious t0 rod or shaft, particularly if asbestos yarn be used, for this material 1s' naturally more or less abrasive. Moreover, improperly lubricated yarn in contact with a reciprocating rod, is soon worked out through the end of Y the stuiiing box, causing leakage. My invention however, provides a new and improved packing and process of manufacturin the same, whereby a superior article is pro uced with less expense, and the characteristics are such that when the packing isvforced into lplace in a stutling box or the like, it becomes molded into a unitary packing ring which is self-lubricatin and under the action of heat will become vu canized, though not to a hard solid condition.

Fig. 1 of the accompanying drawing diagrammatically illustrates a mixing machine in which the various ingredients are mixed.

Fig. 2Jis a diagrammatic sectional view of an extrudin machine which handles the mixed materials in a dough-like mss, extrudes them through a die and twists the 40 dough incident to extrusion.

Fig. 3 is asectional perspective view of the packing with no covermg.

Fig. 4.- is a perspective view illustrating a covering of textile netting which may be'used 45 if desired.

, In the manufacture of the improved packing, pure unvulcanized rubber um and a solvent therefor, are employe together with vulcanizing, anti-oxidant and lubricating. agents, soft shredded metal and long lead and lead alloys, tin, aluminum, brass `ly mixed.

staple bre. The character of metal used will vary according to the uses to which the packing is to be put, illustrations being copper, etc. rlhe libre may be of vegetable nature, such as cotton, ax or substitutes, but long staple asbestos fibre is preferably employed.

Specifically, one advantageous combination of ingredients and proportions, is given below, the percentages relating to weight.

Percent Pure unvulcanized rubber gum 1.5 Shredded soft metal; 48.0 Long staple fibre 17.0 Graphite 27.0 Sulphur 1.0 Palm oil 5.0 Stearic acid .5

The process of manufacture is as follows:

With the use of six gallons of appropriate solvent, the rubber gum is iirst made into a lean solution of about the consistency of milk. This solution is placed in a mixing machine such as that illustrated in Fig. 1 of the drawing, and is agitated by the spiked agitators A therein. These agitators are driven so that the adjacent arms thereof move in opposite directions which is of advantage in producing a carding or drawing action on the libres and other ingredients when Athey are added, thereby eiectively separating them and insuring thorough distribution inl the rubber solution.

The fibres are added to the solution in a finely divided form while the agitators A are in motion and consequently they are thoroughly separated and each receives a coating of the solution. The other ingredients are added in a similar manner, resulting in thorough coating of the ingredients upon which said coating can form and insuring that all of said ingredients shall be thorough- The steps above described, produce a mass of dough-like consistency. This dough is transferred to an extruding machine auch as that illustrated in Fig. 2 and is by this machine, extruded through an appropriate 10 die D. The dough is placed under pressure by a plunger vP or other desired means, and a worm W forces it through the die D. This worm operates within a stationary cylinder C and in addition to extruding the dough through the die D, said worm imparts a twisting actionto the dough as the latter is being extruded. This naturally twists the libre and metal, resulting in a rope-like packing having a twisted formation. v

The extruded packing is placed in containers and passed on to a drying chamber,l in which the solvent is evaporated, leaving a homogeneous substantially dry product, the fibres of which are equally distributed along with the other ingredients, and due to the formation and distribution particularly with regard to the fibres, a bonded product is producedfwhich when in use cannotbe disturbed in the stufing box by existing pressures orV shaft or rod'motions.

The rubber, although'in a very small percenta e, gives to the mass a suiiicient bondrubber the necessary de ree of vulcanization when the packing 1s su jected to high temperatures, but not suflicient to have any other hardening effect upon the packing. In addition to acting as a vulcanizing agent, the sulphur acts to preserve the rubber by preventing oxidation. The stearic acid also functions toward the end of an anti-oxidant as well as constituting a lubricant, and the .palm oil and graphite act as lubricating antifriction materials. The quantity of rubber, is in small ercentage compared with the other ingredlients, yet is a very essential element. The only object in using this rubber is to produce the requisite bonding. Even when using such a small percentage of rubber by mixing the other ingredients with 'the ru ber solution as above described, all fibres and other components parts are equally covered and a homogeneous mass is produced, even with its lubricating properties equally divided and dgtributed over the whole.

The improved packin is suitable for all kinds of equipment whet er of reci rocating or rotary nature and regardless o the materials to be handled, for it is not affected by oils, gases, solvents, acids alkalies, etc. The lubricating medium is so dispersed and intermingled with the other component parts that the packin will retain its lubricating properties inde itely, and it is virtually impossible therefore for the packing to injure an rod, shaft or the like against which it is use I claim f 1. Av process of manufacturin packing rope com rising the steps of orming a dough em odying long stable fibre, extruding the fibre-carrying dough through a die and twisting said bre-carrying dough imei-- soft shredded metal and long staple bre with a lean rubber solution to form a dough; formingpthe dough into single-strand rope shape and twisting said dough during formation of said strand to provide a stron ly bonded product and evaporating the rub er solvent, leaving a substantially dry rope-like 'packing with its rubber content unvulcanized.

4. A process of manufacturing packing rope comprising the steps of mixing vulcanizing, anti-oxidant and lubricating agents, soft shredded metal and long staple fibre into said solution to form a dough; extruding the dough through a die and twisting said dough incident to extrusion to provide a strongly bonded product, and eva orating the solvent, leaving a substantially ry ropelike packing, with its rubber content unvul canized.

5. A packing comprising a homogeneous rope-like mass consisting of unvulcanized rubber, shredded soft metal, long staple fibre, and vulcanizing, anti-oxidantI and lubricat- -ing agents, the rubber constituting a very small percentage of the mixture and acting primarily as a binder instead of a space ills er, the vulcanizing agent being in such small quantity as to prevent vulcanizing of the rubber to a hard state under use-generated heat.

6. A packing comprising a homogeneous rope-like mass consisting of substantially 1.5% unvulcanized rubber, substantially 48% Ashredded soft metal, and approximately 17% long staple libre, the remainder consisting of vulcanizing, anti-oxidant and lubricating agents. L

7. A recess of manufacturing packin comprising thev ste of mixing packing an lubricating ingre ients to form a dough, forming said dough into substantially ropeshape, and placing a textile nettin tube around the rope-shaped dough to comblne the latter without covering an appreciable portion of itsv surface area.

8. A packing comprising a rope-like body of long staple libres, metal fragments and lubricant, and a tubular textile netting around said body covering only an infinitesimal portion of its area. i

9. A process of manufacturing packin rope comprising the steps of forming a doug lll f so

embodying long staple fibre, forming the fibre-carrying dough mto single-strand rope, and twisting said bre-carrymg dough incident to forming said strand, provlding a, strongly bonded product.

In testimony whereof I have hereunto affixed my signature.

HERBERT STANLEY WALKER. 

